GB2492651A

GB2492651A - Locking device to prevent access to a handle in an emergency door

Info

Publication number: GB2492651A
Application number: GB1211869.1A
Authority: GB
Inventors: Ulf Bergman; Peter Gustavsson
Original assignee: Scania CV AB
Current assignee: Scania CV AB
Priority date: 2011-07-05
Filing date: 2012-07-04
Publication date: 2013-01-09
Anticipated expiration: 2032-07-04
Also published as: GB2492651B; GB201211869D0; SE1150632A1; SE535964C2

Abstract

A locking device 105 for an emergency door of a vehicle, e.g. a bus, the device comprises a cover 1 which in a first state hinders access to the emergency door's handle 106 and in a second state allows access to the handle 106, the cover plate has a lock having a first and second locking element, the lock controlled by a control unit. The locking device 105 preferably is controlled so that the cover 1 is locked in the first state when the vehicle's speed is below 5 km/h. A baseplate 3 may be used to fasten the locking device to the emergency door 101 or to the glazing of an emergency door. The lock may be an electromagnet 5 which engages with a metal plate 4a, or a moveable piston (6 Fig 8b) which engages with a recess (8 Fig 8b). The piston may be moved through use of a solenoid or air cylinder. The cover prevents unauthorised use of the door handle when the vehicle is in motion.

Description

LOCKING DEVICE TO PREVENT ACCESS TO A HANDLE IN AN

EMERGENCY DOOR

TECHNICAL FIELD

The invention relates to a locking device for making it possible to reach the handle of an emergency door of a vehicle, and to an emergency door and a vehicle with such a locking device.

BACKGROUND

Certain types of buses are provided with emergency doors to facilitate evacuation of passengers. This applies in particular to buses which have only one door, most commonly situated forward. While emergency doors need to be openable in the event of accidents, misuse of such a door by it being opened when there is no need for evacuation has as far as possible to be prevented. It is particularly dangerous if an emergency door is opened when the vehicle is in motion and there is at the time no need for evacuation. Ordinary doors such as those on buses are operated by compressed air, and in an emergency situation a valve is opened such that the compressed air system empties and the door can then be opened. In contrast, emergency doors are most commonly operated mechanically, by means of an ordinary handle. As such a handle is more readily accessible for unauthorised use, it is provided with a locking device to protect the opening mechanism. In an emergency situation the first step is open the locking device, whereupon the opening mechanism becomes usable.

Known locking devices comprise an air cylinder with a piston which moves into part of the door's actual opening mechanism. When the door is to be opened, the cylinder is controlled so that the piston leaves its locking position. As the known locks engage with part of the actual opening mechanism, there is risk of the opening mechanism being destroyed if anyone tries to force the locking device. "Forcing" means attempting to open the locking device by physical force. People may for example behave irrationally in an emergency situation, possibly failing to see the aperture for the locking device and nevertheless trying to open the emergency door.

This may result in the piston becoming deformed such that it cannot leave its locking position and the emergency door's opening mechanism then also becomes unusable. There is then risk of the emergency door being impossible to open because the actual opening mechanism is blocked. It being impossible to open the emergency door may result in not all of the passengers managing to leave the bus in time, so an accident might have more serious consequences than if the emergency door's opening mechanism was intact.

Rules are shortly coming into force within, for example, the EU for the emergency door to be impossible to open when the vehicle is moving faster than a certain speed, in this case 5 km/h. This requirement is intended to reduce the risk of accidents due to emergency doors being opened unnecessarily when the vehicle is in motion.

OBJECT OF THE INVENTION

An object of the invention is to propose a device pertaining to an emergency door for vehicles which solves the problems of the state of the art. The invention proposes in particular a locking device for emergency doors which does not prevent their being opened by forcing the locking device and which is safer than known devices. The invention also proposes a locking device which prevents the emergency door from being opened at above a limit speed of the vehicle.

SUMMARY OF THE INVENTION

According to the invention, these problems are solved by a locking device for hindering access to a handle of an emergency door of a vehicle, comprising a movable cover which is attached to the emergency door and which encloses the handle, which cover in a first position is locked and cannot move relative to the handle, and in a second position is unlocked and can move relative to the handle.

The locking device comprises locking means with a first element situated within the cover, a second element attached to the emergency door or the vehicle, and a control unit to control the locking means between the first and second positions.

The fact that the locking device does not engage with any parts of the opening mechanism of the emergency door reduces the risk of its being damaged and rendering the emergency door impossible to open. Any forcing of a locking device according to the invention thus only risks causing damage to the cover, making it still possible to forcibly remove the cover and leaving the opening mechanism intact. The fact that the handle is enclosed by the cover means that it is not accessible when the cover is closed. The cover then masks substantially the whole handle. The cover may be both locked and unlocked in the closed state.

According to an embodiment of the invention, the control unit controls the locking means on the basis of the vehicle's speed, which is a simple way of automatically controlling whether access to the emergency door is to be possible or not.

Information about the vehicle's speed is readily available on board and can be used with reasonable accuracy to predict how the driver intends to drive the vehicle. When for example the vehicle is moving at below a limit speed, it is very likely to come to a halt shortly, and when it is moving at above a limit speed it is very likely to continue accelerating and travel on. This limit speed may for example be 5 km/h. A device according to this embodiment minimises the risk of the emergency door being opened unnecessarily when the vehicle is moving at above a certain speed, since the cover will then be locked to the emergency door or the vehicle and the opening mechanism will not be accessible. If the locking device has to be forced, there is thus no risk of damage to the actual opening mechanism. Examples of situations where the locking device may have to be forced are where evacuation is necessary at a time when the vehicle is moving at above a limit speed or where a fault causes the cover to remain locked even at below a limit speed.

According to another embodiment of the invention, the locking means is an electromagnet whose first element is a disc fastened to a rod and second element is a holding magnet. This makes it easy to activate the locking device since all that is required is for the control unit to supply current to the holding magnet. If access to the handle of the emergency door becomes necessary in a situation where the cover is locked, all that has to be done to release the cover is to overcome the force of the holding magnet. This type of locking means is also robust and comprises few parts, rendering it durable and reducing the risk of the locking device disintegrating.

According to a further embodiment of the invention, the first element is a recess in the cover and the second element is a piston. In the first state the cover is then mechanically locked to the emergency door or the vehicle. In the event of the locking device being forced, the piston may become deformed, but since the emergency door's opening mechanism does not move into the locking device the only risk is of damage to the cover. It remains possible to reach the handle by smashing the cover and to then be able to open the door.

The piston may be driven by an air cylindei, by solenoid, i.e. an electromagnet, or by an electric motor. All of these alternatives are simple and inexpensive standard components which can with little trouble or difficulty be used to achieve the desired effect.

The cover and the other parts of the locking means may also be attached to a baseplate fastened to the emergency door or the vehicle, making it easy to fit the locking device since the baseplate, the cover and the other parts of the locking means can be delivered in the form of a preassembled unit. It would also be easier to attach the locking device to, for example, the windowpane of the emergency door, since the baseplate might be adhesively bonded to the windowpane. The baseplate then also serves as a fastening point for the hinge of the cover.

The invention relates also to an emergency door with a locking device as above and to a vehicle with such an emergency door. It is particularly advantageous if the invention is employed on a bus, since buses often carry many persons and there is great need to evacuate them in the event of an accident.

LIST OF DRAWINGS

Figure 1 depicts schematically a vehicle according to the invention.

Figure 2 depicts schematically an emergency door according to the invention.

Figure 3 depicts schematically a section of a device according to the invention in a closed state.

Figure 4 depicts the device in Figure 3 in an open state.

Figure 5 is a perspective view of the device in Figure 3 in a closed state.

Figure 6 depicts the device in Figure 5 in an open state.

Figure 7 depicts schematically an emergency door according to the invention with associated control unit.

Figure 8a depicts schematically an alternative embodiment of the invention.

Figure 8b depicts a section c-c in Figure 8a.

DETAILED DESCRIPTION OF THE INVENTION

Figure 1 depicts schematically a vehicle 100 according to the invention. In this drawing the vehicle is a bus but it might also be some other vehicle equipped with an emergency door. Figure 2 depicts an emergency door 101 provided with a window frame 110 and a windowpane 103 fitted in the frame 110. The emergency door 101 is also equipped with a mechanical opening mechanism 104 protected by a locking device 105. The opening mechanism 104 is fastened in the frame 102 of the emergency door 101.

The emergency door's 101 opening mechanism 104 is activated by means of a handle 106 locked to, for rotation with, a rod 107 (see Figure 6). The rod 107 has its two ends connected to the emergency door's 101 locking pistons 108. When the handle 106 is rotated, the rod 107 also rotates, thereby drawing in the locking pistons 108 and making it possible to open the emergency door 101.

The locking device 105 is depicted in more detail in Figure 3. It comprises a baseplate 3 to which a cover 1 is attached. The baseplate 3 is fastened to the emergency door's 101 windowpane 103, e.g. by adhesive bonding, but other equivalent ways of fastening the baseplate 3 are possible.

It is also conceivable for the cover 1 and the other parts of the locking means to be attached directly to the emergency door 101, i.e. with no baseplate. The cover 1 need not be attached to the emergency door's windowpane 103 as depicted in the drawings, as it might also be attached to the lower portion of the emergency door 101. An important consideration in the location of the cover 1 and the handle 106 is that they be readily accessible when the need to open the emergency door 101 arises.

It is also conceivable for the locking device 105 to be attached to the vehicle 100 and not to the emergency door 101.

The cover 1 is so configured as to substantially enclose the whole of the emergency door's handle. In a closed state the cover 1 encloses the handle 106 in such a way that the handle 106 cannot be reached. The cover 1 may for example be made of extruded aluminium but strong plastic or some other suitable material is also possible. The drawing shows the cover 1 fastened hingingly to the baseplate 3 by, for example, a hinge 2, but it is also conceivable for the cover 1 and the baseplate 3 to be joined together by some other mechanism which allows the cover to be rotated relative to the baseplate 3. It is also conceivable for the cover to be fastened to the baseplate in such a way that it can be released from it completely.

The locking means comprises a first element 4, 4a situated within the cover 1 and a second element 5 fastened to the baseplate 3. In the embodiment in Figures 3-6, the locking means is an electromagnet comprising a holding magnet 5 and a disc 4a mounted on a carrier 4. When current passes through the holding magnet 5, the latter becomes magnetic and holds the disc 4a firmly. When the holding magnet 5 is not energised it is not magnetic and the disc 4a is free to move relative to it. This also makes it possible for the cover 1 to be rotated relative to the baseplate 3 and for the opening mechanism 104 to become accessible. The disc 4a is supported on the rod 4 by a ball joint or equivalent so that it can rock on the end of the rod 4. For good contact of it with, and hence firm force holding it to, the holding magnet 5, the disc 4a needs to abut tightly. The ball joint therefore allows certain movements of the disc 4a relative to the holding magnet, rendering the locking function independent of tolerances during manufacture and fitting.

Another embodiment of the invention is depicted in Figures 8a-8b. Instead of using an electromagnet to lock the cover 1 to the baseplate 3, this is achieved by a piston 6 being inserted in a recess 8 in the cover 1. In position A the piston is inserted in the recess and the cover 1 is locked to the baseplate 3. In position B the piston 6 is not in the recess and the cover 1 can move relative to the baseplate 3. The piston 6 may be activated by an air cylinder 7, a solenoid or an electric motor fastened to the baseplate 3. Even if the emergency door's 101 locking device in this embodiment was forced, there would be no risk of the opening mechanism 104 being destroyed, since the piston 6 only locks in the cover 1.

A common feature of all these types of locking means is being in a non-locking state when the vehicle 100, and hence also the locking device 105, are not energised.

The power supply to the locking means is controlled by a control unit 109 depicted in Figure 7. This control unit 109 may be a separate control unit or the locking means may be controlled by a central control unit on board the vehicle. The control unit 109 receives information about the vehicle's speed via an on-board speed sensor 42.

When the vehicle's speed is above a limit value, e.g. 5 km/h, the control unit 109 sends signals to the locking device 105 to put it into a locking state. This is done either by energising a holding magnet 5 or by activating a solenoid, an air cylinder or an electric motor to move a piston 6 to a locking position in a recess 8 in the cover 1.

The emergency door's 101 opening mechanism 104 will then not be accessible for unauthorised use. If anyone does try to open the emergency door 101, there is no risk of damage to the opening mechanism 104. When the vehicle is moving at below the limit speed, the control unit 109 sends signals to the locking device 105 for it to be put into a non-locking state, i.e. the holding magnet 5 becomes de-energised and therefore non-magnetic or a piston is moved to a non-locking position by means of a solenoid, an air cylinder or an electric motor. The cover 1 can then be opened and the emergency door's 101 handle 106 become accessible.

The invention results in a locking device 105 for the handle 106 of an emergency door 101 which handle 106 is enclosed by a cover 1 which can be opened at vehicle speeds below 5 km/h but is locked at speeds over 5 km/h. If anyone does try to open the cover 1 when it is locked, there is no risk of damage to the emergency door's 101 opening mechanism 104 and no possibility of the emergency door 101 opening. In the event of damage to the locking device 105, there always remains the possibility of forcibly removing the whole cover in order to reach the opening mechanism 104.

The invention is of course in no way restricted to the embodiments described above, since many possibilities for modifications thereof are likely to be obvious to one skilled in the art without thereby having to deviate from the invention's basic concept such as defined in the attached claims.

Claims

<claim-text>CLAIMSA locking device (105) for hindering access to a handle (106) of an emergency door (101) of a vehicle (100) characterised by a movable cover (1) attached directly or indirectly to the emergency door (101) or the vehicle (100) and enclosing the handle (106), which cover (1) in a first state is locked against movement relative to the handle (106) and in a second state is unlocked and free to move relative to the handle (106), in that the locking device (105) comprises locking means (4, 4a, 5, 6, 8) with a first element (4, 4a, 8) situated within the cover (1) and a second element (5, 6) attached directly or indirectly to the emergency door (101) or the vehicle (100) and by a control unit (109) which controls the locking means (4, 4a, 5, 6, 8) between the first and second states.</claim-text> <claim-text>2. A locking device (105) according to claim 1, characterised in that the control unit (109) controls the locking means (4, 4a, 5, 6, 8) on the basis of the vehicle's speed.</claim-text> <claim-text>3. A locking device (105) according to claim 2, characterised in that the control unit (109) puts the locking means (4, 4a, 5, 6, 8) into the second state when the vehicle's speed is below 5 km/h.</claim-text> <claim-text>4. A locking device (105) according to any one of the foregoing claims, characterised in that the locking means is an electromagnet comprising as its first element a disc (4a) mounted on a rod (4) and as a second element a holding magnet (5).</claim-text> <claim-text>5. A locking device (105) according to any one of claims 1 -3, characterised in that the first element of the locking means is a recess (8) and its second element a piston (6).</claim-text> <claim-text>6. A locking device (105) according to claim 5, characterised in that the control unit (109) controls the piston's (6) position by means of a solenoid.</claim-text> <claim-text>7. A locking device (105) according to claim 5, characterised in that the control unit (109) controls the piston's (6) position by means of an air cylinder (7).</claim-text> <claim-text>8. A locking device (105) according to any one of the foregoing claims, characterised in that the cover (1) and the other parts (5, 6) of the locking means are fastened to a baseplate (3) which is itself fastened to the emergency door (101) or the vehicle (100).</claim-text> <claim-text>9. A locking device (105) according to claim 8, characterised in that the baseplate (3) is fastened to the emergency door's (101) windowpane (103).</claim-text> <claim-text>10. An emergency door (101) for vehicles, characterised by being provided with a locking device (105) according to any one of the foregoing claims.</claim-text> <claim-text>11. A vehicle (100) characterised by being provided with an emergency door (101) according to claim 8.</claim-text> <claim-text>12. A vehicle (100) according to claim 11, characterised by being a bus.</claim-text> <claim-text>13. A locking device substantially as herein before described and with reference to the accompanying drawings.</claim-text> <claim-text>14. An emergency door for vehicles substantially as herein before described and with reference to the accompanying drawings.</claim-text> <claim-text>15. A vehicle substantially as herein before described and with reference to the accompanying drawings.CLAIMS1. A locking device (105) for hindering access to a handle (106) of an emergency door (101) of a vehicle (100) characterised by a movable cover (1) attached directly or indirectly to the emergency door (101) or the vehicle (100) and enclosing the handle (106), which cover (1) in a first state is locked against movement relative to the handle (106) and in a second state is unlocked and free to move relative to the handle (106), in that the locking device (105) comprises locking means (4, 4a, 5, 6, 8) with a first element (4, 4a, 8), wherein the locking means is enclosed within the cover (1), and a second element (5, 6) attached directly or indirectly to the emergency door (101) or the vehicle (100), and by a control unit (109) which controls the locking means (4, 4a, 5, 6, 1 8) between the first and second states. CoCJ
2. A locking device (105) according to claim 1, characterised in that the control unit (109) controls the locking means (4, 4a, 5, 6, 8) on the basis of the vehicle's speed.
3. A locking device (105) according to claim 2, characterised in that the control unit (109) puts the locking means (4, 4a, 5, 6, 8) into the second state when the vehicle's speed is below 5 km/h.
4. A locking device (105) according to any one of the foregoing claims, characterised in that the locking means is an electromagnet comprising as its first element a disc (4a) mounted on a rod (4) and as a second element a holding magnet (5).
5. A locking device (105) according to any one of claims 1 -3, characterised in that the first element of the locking means is a recess (8) and its second element a piston (6).
6. A locking device (105) according to claim 5, characterised in that the control unit (109) controls the piston's (6) position by means of a solenoid.
7. A locking device (105) according to claim 5, characterised in that the control unit (109) controls the piston's (6) position by means of an air cylinder (7).
8. A locking device (105) according to any one of the foregoing claims, characterised in that the cover (1) and the other parts (5, 6) of the locking means are fastened to a baseplate (3) which is itself fastened to the emergency door (101) or the vehicle (100).
9. A locking device (105) according to claim 8, characterised in that the baseplate (3) is fastened to the emergency door's (101) windowpane (103).
10. An emergency door (101) for vehicles, characterised by being provided with a locking device (105) according to any one of the foregoing claims.
11. A vehicle (100) characterised by being provided with an emergency door (101) according to claim 8.
12. A vehicle (100) according to claim 11, characterised by being a bus.
13. A locking device substantially as herein before described and with reference to the accompanying drawings.
14. An emergency door for vehicles substantially as herein before described and with reference to the accompanying drawings.
15. A vehicle substantially as herein before described and with reference to the accompanying drawings.</claim-text>